XVal operators

Truthyness and falsyness

Falsey	Truthy
false	true
0	All other numbers
"" empty-string	All other strings
null	() unit-symbol
	All list values
	All object values

If-then-else operator

a ? b : c   // This stands for “if a then b else c”

Short circuit operators

The || and && operators are truthy based value short circuit operators.

a && b returns a if a is falsey, or b if a is truthy.

a || b returns a if a is truthy, or b if a is falsy. This can be used for boolean logic (price < 100 && quantity < 3), for value selection based on conditions (price < 100 && ‘cheap’ || ‘expensive’), or for value coalescing (nickname || fullname).